During the 20th century, advances in medicine and access to fresh water, better food and improved living conditions increased the health and lifespans of million of people across the planet. Now climate change is rolling back some of those gains…and the effects are likely to get worse over the next century.

As animals, bacteria, fungi and algae struggle to adapt in a warming world, they are encroaching ever more rapidly into areas of the globe inhabited by humans. As Covid-19 already proved to us, these changes can have devastating consequences for humanity.

And while species that can be detrimental to our health are expanding their ranges, species we depend on for sustenance are disappearing. At the same time, we ourselves are being displaced at an alarming rate- 20 million people per year– creating ever more stress in areas where displaced folks need housing, food and medical attention (see the current migrant crisis for just one close-to-home example).

All these factors add up to a dangerous situation when it comes to human health. Diseases we thought we had eradicated are coming back, and ones we never had to contend with before are cropping up.

“This is not just something off in the future,” Neil Vora, a physician with the nonprofit Conservation International, said. “Climate change is here. People are suffering and dying right now.”

You can read about this on Grist.org here.